Southwest flow ahead of a strong cold front produced strong gusty gradient winds across western Colorado.
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The episode as NWS GJT wrote it up.
Southwest flow ahead of a strong cold front produced strong gusty gradient winds across western Colorado.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Grand Junction, CO wrote its last area forecast discussion before the first event at Sep 29, 9:36 AM MST, 1 hour 55 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND JUNCTION CO 1036 AM MDT SAT SEP 29 2007 .UPDATE...QUICK UPDATE TO THE FORECAST THIS MORNING TO INCLUDE A WIND ADVISORY FOR THE LOWER ELEVATIONS OF WESTERN COLORADO AND SOUTHEAST UTAH. WIND SPEEDS HAVE STEADILY INCREASED THIS MORNING... WITH A FEW SITES HITTING LOW END ADVISORY CRITERIA WITHIN THE PAST HOUR. WITH HIGH BASED SHOWERS DEVELOPING OUT AHEAD OF THE FRONT... EXPECT SIGNIFICANT WIND GUSTS TO HIT THE VALLEY FLOORS THROUGHOUT THE AFTERNOON HOURS. THIS ADVISORY WILL BE IN EFFECT UNTIL 6 PM THIS EVENING. HAVE ALSO ADJUSTED SKY COVER AND POPS TO FIT CURRENT TRENDS. && .SHORT TERM...TODAY THROUGH SUNDAY NIGHT... TODAY AND TONIGHT...A FAST-MOVING COLD FRONT AND UPPER TROUGH WILL MOVE THROUGH THE FORECAST AREA TODAY. GFS AND NAM HAVE SIMILAR TIMING AND INTENSITY WITH THIS STORM IN THE FIRST 48 HRS. BOTH PROJECT THE SURFACE COLD FRONT AT THE UT/CO BORDER AROUND 00Z THIS AFTERNOON... BUT THIS MIGHT BE A BIT LATE. AT 6 AM IT WAS ALREADY INTO NE UTAH AND APPROACHING SLC. BELIEVE THE COLD FRONT WILL BE IN NE UTAH ABOUT MID AFTERNOON AND THROUGH THE NORTHERN HALF OF THE AREA ABOUT 9 PM TONIGHT. IT SHOULD PUSH MORE SLOWLY THROUGH THE SOUTHERN HALF OF THE FORECAST AREA...MOVING EAST OF ARCHULETA COUNTY BEFORE SUNRISE. THE FRONT PACKS QUITE A PUNCH WITH A WELL-PACKED THERMAL FIELD AND STRONG PRE- AND POST-FRONTAL WINDS AND AN ABRUPT WIND SHIFT WITH FRONTAL PASSAGE. BELIEVE SURFACE WINDS AND WIND GUSTS WILL APPROACH BY NOT MEET WIND ADVISORY CRITERIA EXCEPT IN THOSE ISOLATED AREAS WHERE TERRAIN FAVORABLY FOCUSES SW WINDS AHEAD OF THE FRONT AND NW WINDS BEHIND IT. MOISTURE IS THE ONLY INGREDIENT THIS SYSTEM LACKS... WITH THE BEST AVAILABLE MOISTURE TRAVELING OVER THE NORTHERN HALF OF THE AREA...GENERALLY NORTH OF A LINE FROM GUNNISON TO MONTROSE TO MOAB. THE COLDER AIRMASS WILL BRING SNOW TO THE NORTHERN AND CENTRAL MOUNTAINS OF CO AND UT...WITH SNOW LEVELS FALLING TO 8K BY EARLY SUNDAY MORNING. WILL EXPECT RELATIVELY LIGHT AMOUNTS OF LESS THAN 4 INCHES DUE TO THE SYTSEMS QUICK PACE. SUNDAY AND SUNDAY NIGHT...DRIER AND COOLER CONDITIONS MOVE IN QUICKLY BEHIND THE SYSTEM. SUNDAY MORNING SHOULD BE COOL...BUT LOW TEMPS SUNDAY NIGHT WILL BE COOLER. .LONG TERM...MONDAY THROUGH SATURDAY... NEXT SYSTEM WILL MOVE OVER EASTERN UTAH AND WESTERN COLORADO LATE MONDAY INTO EARLY TUESDAY. THIS SETS UP A SOUTHWESTERLY FLOW ALOFT AND HELPS TO INCREASE MOISTURE SLIGHTLY. PW VALUES INCREASE FROM BELOW 0.25 INCHES TO JUST ABOVE HALF AN INCH NORTH AND NEAR AN INCH ALONG THE SOUTH. THE NAM IS MORE GENEROUS WITH THE MOISTURE THAN THE GFS. THE NAM SEEMS OVER DONE BRINGING A STRONG TAP OF SUB TROPICAL MOISTURE...A BLEND OF GULF AND EASTERN PAC STORM ALONG BAJA...INTO THE CENTRAL PORTION OF OUR CWA. THE GFS KEEPS THE PAC MOISTURE AND STORM FARTHER SOUTH AND THE GULF MOISTURE FARTHER SOUTHEAST. THEREFORE WILL INCREASE POPS FOR MON NIGHT BUT KEEP A BIAS TOWARD THE GFS. MODELS ARE IN FAIRLY GOOD AGREEMENT IN THE TIMING OF THIS NEXT TROUGH OVER THE GREAT BASIN BY 0Z TUE...OVER THE CENTRAL ROCKIES BY 12Z TUE AND THEN BY 0Z WED THE TROUGH IS WELL EAST OF CO AND THE CWA IS UNDER SLIGHT NORTHWESTERLY FLOW ALOFT. TEMPERATURE WILL COOL DOWN WITH THE ASSOCIATED COLD FRONT PASSAGE BUT WARM AGAIN BY MID WEEK. WINDS WILL INCREASE OVER THE FORECAST AREA TURNING SOUTHWEST IN FRONT OF THE TROUGH AND THEN BECOMING WEST TO NORTHWEST AFTER THE FRONT. RELATIVELY DRY PATTERN FOR MID WEEK AS THE FLOW ALOFT IS MORE ZONAL AND THE MAIN JET AXIS STAYS NORTH OF THE CWA. EXPECT AFTERNOON TO BECOME BREEZY AS WINDS MIX TO THE SURFACE. ANOTHER TROUGH DEVELOPS OVER THE PAC NORTHWEST AND DIGS AS IT DEVELOPS. GFS IS MORE PROGRESSIVE AND WANTS TO KICK THE SYSTEM EAST FASTER THAN THE EC. EC SOLUTION IS STILL SLOWER AND HOLD OFF ON MOVING THE TROUGH EASTWARD. CONFIDENCE IS LOW THIS FAR OUT TO JUMP ON THE GFS SO WILL CONTINUE THE CURRENT FORECAST TREND. && .AVIATION... POTENTIAL FOR LOCAL MVFR CONDITIONS EARLY THIS AFTERNOON BECOMING WIDESPREAD IN THE MOUNTAINS THIS EVENING AS SHOWERS AND THUNDERSTORMS INCREASE FROM ISOLATED TO SCATTERED. SNOW IN THE MOUNTAINS LATER THIS AFTERNOON THROUGH TONIGHT WILL PRODUCE LOCAL IFR CONDITIONS. SOME LOW LEVEL WIND SHEAR LIKELY TO EXIST LATE THIS AFTERNOON AND THIS EVENING AS FLOW NEAR 9000 FEET MSL IS PROGGED TO STRENGTHEN TO AROUND 40 KTS ACROSS EASTERN UTAH AND MUCH OF WESTERN COLORADO. && .GJT WATCHES/WARNINGS/ADVISORIES... .CO...WIND ADVISORY UNTIL 6 PM TODAY FOR ZONES 01/02/06/07/11/20/21. .UT...WIND ADVISORY UNTIL 6 PM TODAY FOR ZONES 22/27/29. UPDATE...JDC SHORT TERM...CJC/DJC LONG TERM....AS AVIATION.....DJC/CJC
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GRAND JUNCTION CO 1037 AM MDT SAT SEP 29 2007 COZ001>014-017>023-UTZ022>025-027>029-301145- ANIMAS RIVER BASIN-ARCHES/GRAND FLAT-CANYONLANDS/NATURAL BRIDGES- CENTRAL COLORADO RIVER BASIN- CENTRAL GUNNISON AND UNCOMPAHGRE RIVER BASIN- CENTRAL YAMPA RIVER BASIN-DEBEQUE TO SILT CORRIDOR- EASTERN UINTA BASIN-EASTERN UINTA MOUNTAINS- ELKHEAD AND PARK MOUNTAINS-FLAT TOPS- FOUR CORNERS/UPPER DOLORES RIVER- GORE AND ELK MOUNTAINS/CENTRAL MOUNTAINS-GRAND AND BATTLEMENT MESAS- GRAND VALLEY-LA SAL AND ABAJO MOUNTAINS-LOWER YAMPA RIVER BASIN- NORTHWEST SAN JUAN MOUNTAINS-PARADOX VALLEY/LOWER DOLORES RIVER- ROAN AND TAVAPUTS PLATEAUS-SAN JUAN RIVER BASIN-SOUTHEAST UTAH- SOUTHWEST SAN JUAN MOUNTAINS-TAVAPUTS PLATEAU- UNCOMPAHGRE PLATEAU AND DALLAS DIVIDE-UPPER GUNNISON RIVER VALLEY- UPPER YAMPA RIVER BASIN-WEST ELK AND SAWATCH MOUNTAINS- 1037 AM MDT SAT SEP 29 2007 ...WIND ADVISORY UNTIL 6 PM MDT TODAY FOR THE LOWER ELEVATIONS OF WESTERN COLORADO AND SOUTHEAST UTAH... THIS HAZARDOUS WEATHER OUTLOOK IS FOR EASTERN UTAH AND WESTERN COLORADO. .DAY ONE...TODAY AND TONIGHT SOUTHWEST WINDS OF 25 TO 45 MPH WITH GUSTS TO 55 MPH ARE EXPECTED THIS AFTERNOON AND EVENING AS A COLD FRONT MOVES THROUGH THE AREA. SCATTERED THUNDERSTORMS PRODUCING STRONG GUSTY WINDS...CLOUD TO GROUND LIGHTING...AND SMALL HAIL WILL OCCUR THIS AFTERNOON AND EVENING...WITH SNOW SHOWERS IN THE MOUNTAINS ABOVE ABOUT 8500 FEET. SNOW ACCUMULATIONS OF 2 TO 4 INCHES ARE POSSIBLE ABOVE 9500 FEET ACROSS SOME OF THE MOUNTAINS OF NORTHEAST UTAH AND NORTHWEST AND CENTRAL COLORADO BY LATE TONIGHT. ROADS OVER HIGH MOUNTAIN PASSES MAY BECOME LOCALLY ICY AND SNOWPACKED. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY ISOLATED SNOW SHOWERS WILL DISSIPATE OVER THE NORTHWEST COLORADO MOUNTAINS SUNDAY MORNING. THE NEXT CHANCE OF VALLEY RAIN SHOWERS AND THUNDERSTORMS...AND MOUNTAIN THUNDERSTORMS WITH RAIN AND SNOW SHOWERS...COMES ON MONDAY AND TUESDAY WHEN ANOTHER PACIFIC STORM MOVES THROUGH THE AREA. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED TODAY OR TONIGHT. CUOCO/COLTON
The national radar mosaic for the moment the first event began.
1 strong wind. Local standard time, as filed.
Strong southwest winds with gusts of 40 to 52 mph buffeted the Grand Valley. The strong winds uprooted a 25 foot tree.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2007Every state in 2007This day in weather historyWarnings in Colorado, September 2007
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 60582.